Method for producing rubber modified thermoplastic resins

Abstract

Disclosed is method for producing a rubber modified thermoplastic reins which comprises carrying out all or a part of the following setps (I) - (VI): (I) a step of mixing the following (A), (B), (C) and thermoplastic resin (2): (A) a latex of graft rubber polymer (1), (B) an organic agent which is capable of dissolving thermoplastic resin (2) and has a solubility in water of 5% by weight or less at a temperature at which (A), (B), (C) and thermoplastic resin (2) are mixed, amount of the organic agent being 10-600% by weight of polymer (4) which is the sum of graft rubber polymer (1) and thermoplastic resin (2) and (C) a water soluble agent capable of coagulating latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1), (II) a step of separating and removing aqueous phase from a two-phase mixture obtained in the mixing step (I), (III) a step of mixing the mixture from which the aqueous phase has been removed at step (II) and the whole or a part of thermoplastic resin (3), (IV) a step of removing a part or the whole of organic agent (B) and remaining water from the mixture obtained at step (III) by a thermal means, (V) a step of mixing the remainder of thermoplastic resin (3) in case a part of thermoplastic resin (3) has been mixed at step (III), and (VI) a step of removing the remainder of organic agent (B) in case only a part of organic agent (B) has been removed at step (IV).

What is claimed is: 
     
       1. A method for producing a rubber modified thermoplastic resin comprising graft rubber polymer (1) produced by emulsion graft polymerization of a vinyl monomer on a rubber latex, thermoplastic resin (2) and thermoplastic resin (3) which comprises carrying out successively the following steps: (I) a step of mixing the following (A), (B), (C) and thermoplastic resin (2): (A) a latex of graft rubber polymer (1),     (B) an organic agent which is capable of dissolving thermoplastic resin (2) and has a solubility in water of 5% by weight or less at a temperature at which (A), (B), (C) and thermoplastic resin (2) are mixed, amount of the organic agent being 10-600% by weight of the sum of the graft rubber polymer (1) and thermoplastic resin (2), (C) a water soluble agent capable of coagulating the latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1).     (II) a step of separating and removing an aqueous phase from a two-phase mixture obtained in the mixing step (I),   (III) a step of mixing the mixture from which the aqueous phase has been removed at step (II) with the whole, a part or none of thermoplastic resin (3),   (IV) a step of removing, by a thermal means, the whole or a part of the organic agent (B) and remaining water from the mixture obtained at step (III) when thermoplastic resin (3) has been mixed at step (III), or removing the whole or a part of the organic agent (B) and remaining water from the mixture from which the aqueous phase has been removed at step (II) when thermoplastic resin (3) has not been mixed at step (III),   (V) a step of mixing the remainder of the thermoplastic resin (3) when a part of the thermoplastic resin (3) has been mixed at step (III) or mixing the whole of the thermoplastic resin (3) when the thermoplastic resin (3) has not been mixed at step (III) and   (VI) a step of removing the remainder of the organic agent (B) from the mixture obtained at step (V) when a part of the organic agent (B) has been removed at step (IV).   
     
     
       2. A method for producing rubber modified thermoplastic resin according to claim 1, wherein the organic agent (B) has the solubility in water of 5% by weight or less at 25° C. 
     
     
       3. A method for producing a rubber modified thermoplastic resin comprising graft rubber polymer (1) produced by emulsion graft polymerization of a vinyl monomer on a rubber latex, thermoplastic resin (2) and thermoplastic resin (3) which comprises carrying out successively the following steps: (I) a step of mixing the following (A), (B), (C): (A) a latex of graft rubber polymer (1),   (B) an organic agent which is capable of dissolving thermoplastic resin (2) added in step (II') and has a solubility in water of 5% by weight or less at a temperature at which (A), (B), (C) and thermoplastic resin (2) are mixed, amount of the organic agent being 10-600% by weight of the sum of the graft rubber polymer (1), and thermoplastic resin (2),   (C) a water soluble agent capable of coagulating the latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1).     (II) a step of separating and removing an aqueous phase from a two-phase mixture obtained in the mixing step (I),   (II') a step of mixing thermoplastic resin (2) with the mixture obtained in step (II) from which the aqueous phase has been removed,   (III) a step of mixing the mixture obtained in step (II') with the whole or none of thermoplastic resin (3),   (IV) a step of removing, by a thermal means, the whole or a part of the organic agent (B) and remaining water from the mixture obtained at step (III) when thermoplastic resin (3) has been mixed at step (III), or removing the whole or a part of the organic agent (B) and remaining water from the mixture from which the aqueous phase has been removed at step (II) when thermoplastic resin (3) has not been mixed at step (III),   (V) a step of mixing the whole of the thermoplastic resin (3) when the thermoplastic resin (3) has not been mixed at step (III) and   (VI) a step of removing the remainder of the organic agent (B) from the mixture obtained at step (V) when a part of the organic agent (B) has been removed at step (IV).   
     
     
       4. A method for producing a rubber modified thermoplastic resin according to claim 3, wherein all of the thermoplastic resin (3) is mixed at step (V). 
     
     
       5. A method for producing a rubber modified thermoplastic resin comprising graft rubber polymer (1) produced by emulsion graft polymerization of a vinyl monomer on a rubber latex and thermoplastic resin (3) which comprises carrying out successively the following steps: (I) a step of mixing the following (A), (B), (C): (A) a latex of graft rubber polymer (1),   (B) an organic agent which has a solubility in water of 5% by weight or less at a temperature at which (A), (B) and (C) are mixed, amount of the organic agent being 10-600% by weight of the graft rubber polymer (1),   (C) a water soluble agent capable of coagulating the latex (A), amount of this agent being 10% by weight or less of graft rubber polymer (1).     (II) a step of separating and removing an aqueous phase from a two-phase mixture obtained in the mixing step (I),   (III) a step of mixing the mixture from which the aqueous phase has been removed at step (II) with the whole, a part or none of thermoplastic resin (3),   (IV) a step of removing, by a thermal means, the whole or a part of the organic agent (B) and remaining water from the mixture obtained at step (III) when thermoplastic resin (3) has been mixed at step (III), or removing the whole or a part of the organic agent (B) and remaining water from the mixture from which the aqueous phase has been removed at step (II) when thermoplastic resin (3) has not been mixed at step (III),   (V) a step of mixing the remainder of the thermoplastic resin (3) when a part of the thermoplastic resin (3) has been mixed at step (III) or mixing the whole of the thermoplastic resin (3) when the thermoplastic resin (3) has not been mixed at step (III) and   (VI) a step of removing the remainder of the organic agent (B) from the mixture obtained at step (V) when a part of the organic agent (B) has been removed at step (IV).   
     
     
       6. A method for producing a rubber modified thermoplastic resin according to claim 3, wherein the organic agent (B) has the solubility in water of 5% by weight or less at 25° C. 
     
     
       7. A method for producing a rubber modified thermoplastic resin according to claim 5, wherein the organic agent (B) has the solubility in water of 5% by weight or less at 25° C.